CVE-2026-40159 (GCVE-0-2026-40159)

Vulnerability from cvelistv5 – Published: 2026-04-10 16:57 – Updated: 2026-04-15 14:48
VLAI
Title
PraisonAI Exposes Sensitive Environment Variable via Untrusted MCP Subprocess Execution
Summary
PraisonAI is a multi-agent teams system. Prior to 4.5.128, PraisonAI’s MCP (Model Context Protocol) integration allows spawning background servers via stdio using user-supplied command strings (e.g., MCP("npx -y @smithery/cli ...")). These commands are executed through Python’s subprocess module. By default, the implementation forwards the entire parent process environment to the spawned subprocess. As a result, any MCP command executed in this manner inherits all environment variables from the host process, including sensitive data such as API keys, authentication tokens, and database credentials. This behavior introduces a security risk when untrusted or third-party commands are used. In common scenarios where MCP tools are invoked via package runners such as npx -y, arbitrary code from external or potentially compromised packages may execute with access to these inherited environment variables. This creates a risk of unintended credential exposure and enables potential supply chain attacks through silent exfiltration of secrets. This vulnerability is fixed in 4.5.128.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-15 14:48 UTC
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-214 - Invocation of Process Using Visible Sensitive Information
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
MervinPraison PraisonAI Affected: < 4.5.128
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